BEIRUT — Al-Qaida's affiliate in Syria, the Nusra Front, captured most of the northwestern city of Idlib from government forces Saturday, sweeping into neighborhoods in the center of the city in a powerful blow to President Bashar Assad's government, opposition activists and the group said.
The Nusra Front is leading a group of ultra-conservative rebels in a major offensive that began earlier this week to take Idlib, near the border with Turkey. If the city falls, it would be the second provincial capital and major urban center lost by President Bashar Assad's forces in the four-year-old conflict.
The eastern city of Raqqa fell to rebels, including the Nusra Front, in March 2013. It was subsequently taken over by Nusra's rival, the Islamic State group, which has since declared the city its de facto capital.
The Britain-based Syrian Observatory for Human Rights said rebel fighters seized control of most of Idlib in a push Friday evening and early Saturday after collapsing government forces withdrew to their bases and several other buildings in the city.
The group, which relies on an extensive network of activists across Syria, said heavy fighting continued Saturday amid heavy artillery shelling from both sides. The Local Coordination Committees, another opposition activist collective in Syria, also reported the "almost complete" capture of large parts of Idlib by the rebels.
An unnamed Syrian military official quoted by state-run news agency SANA said army forces were fighting "fierce battles" against "armed terrorist groups" to regain control in Idlib, adding that the opposing side suffered heavy losses. In an indication of the gravity of the situation, SANA also said the army is repositioning forces and units in the city to face "thousands of terrorists crossing the border from Turkey."